document.write( "Question 864459: A family drives at 55 kilometers an hour toward a city 660 kilometers away. A second family leaves an hour later and drives 60 kilometers an hour. Which family will arrive at its destination first, and how much later does the other arrive? \n" ); document.write( "
Algebra.Com's Answer #521035 by LinnW(1048)\"\" \"About 
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Let's find out how long it will be until the two families are at the
\n" ); document.write( "same location.
\n" ); document.write( "At some distance d , we have for the first family
\n" ); document.write( "d = 55 km * t + 55*( 1 hour )
\n" ); document.write( "and for the second family,
\n" ); document.write( "d = 60 km * t
\n" ); document.write( "So 55*t + 55 = 60*t
\n" ); document.write( "subtract 55t from each side
\n" ); document.write( " 55 = 5t
\n" ); document.write( "divide each side by 5
\n" ); document.write( " 11 = t
\n" ); document.write( "So for the first family d = 55*11 + 55 = 660
\n" ); document.write( "The first family has traveled for a total of 12 hours,
\n" ); document.write( "The first hour before the second family started plus 11 hours.
\n" ); document.write( "The second family travels the 660 miles in 11 hours.
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\n" ); document.write( "The two families arrive at the same time.
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